A typical installation for a commercial microwave oven is a fast-food franchise outlet where it is common to require exact cooking times for each food offered to assure uniformity of results. At the same time it is common for such an outlet to have employees such as high school students who are not skilled in cooking. These needs have been met by commercial microwave ovens having a set of input switches or buttons which enable an unskilled oven operator to select from among a predetermined set of cooking times. In such ovens, ease and speed of selection of the proper heating or cooking cycle has been paramount. In contrast to a consumer oven operation where a number of switch actuations are required to initiate a cooking cycle, a commercial oven generally requires only one switch actuation for operation according to a particular cycle. However such prior commercial ovens lacked "front programmability". The predetermined cooking times were fixed in the oven during manufacture, and in order to change the time for a particular cycle in such ovens it was necessary to at least partially disassemble the oven and make adjustments to or replacements of parts within the oven controller. Such procedure requires the presence of trained service personnel and is thus inconvenient and costly to a microwave oven owner. However the need to change the cooking times continued to grow. Many fast-food chains revise their menus from time to time, substituting new items for old to improve their offerings. Because changing even a single cooking time in a prior art commercial oven was difficult, it did not meet the needs of these oven owners.